With the end of his distinguished career in government set for late June, Defense Secretary Robert Gates would be justified in taking a slow, satisfying victory lap. Gates focused the Pentagon on fighting current wars instead of procuring shiny new weapons for unlikely future conflicts. He backed the right strategy and generals in Iraq — a nation that the anti-Iraq-war president now concedes demonstrates “the promise of a multiethnic, multisectarian democracy.” Against considerable opposition within the administration, Gates prevailed upon President Obama to give a serious counterinsurgency campaign a shot at success in Afghanistan.

But instead of collecting laurels, Gates has used his last weeks in office to issue a direct warning to his successor, to Congress and to the president. In response to proposals for deep but vaguely defined defense cuts, Gates asks: “If you want to change the size of the budget in a dramatic way, what risk are you prepared to take in terms of future threats to the country?”

Michael Gerson is a nationally syndicated columnist who appears twice weekly in The Post. View Archive

The administration and many in Congress seem to view defense as an easy target for across-the-board reductions. Gates is waging his final war against such abstraction. Decisions on defense spending, in his view, must be based on strategy, not on budget mathematics. “Right now, the process is just the reverse,” he argues. “Everybody’s doing math and not strategy.”

The most obvious defense cuts have already been made. Gates has gotten rid of big-ticket weapons programs criticized for their cost, performance and relevance — the Marine expeditionary fighting vehicle, the next-generation Navy cruiser, the Air Force search-and-rescue helicopter, the airborne missile defense laser, the infamous presidential helicopter. He limited the purchase of F-22s to a realistic level. He killed the Army Future Combat Systems, which used vehicles that were thin-skinned, flat-bottomed magnets for improvised explosive devices.

Reductions get harder from here. Some of America’s most expansive military commitments are not made in the Middle East but rather in the military’s health care, compensation and retirement systems. Health costs in the defense budget have risen from $19 billion in 2001 to more than $50 billion today. The military retirement system is appropriately generous. But the possibility of retiring at age 37 with full benefits — following 20 years of service — seems generous beyond normal bounds.

Various deficit-reduction commissions have proposed increasing the age of eligibility for military retirement pay to 57, encouraging military recruitment and retention with targeted bonuses instead of broad pay increases, and cutting costs in the military’s Tricare health plan. “There are no sacred cows,” says Gates. “Everybody knows that we’re being eaten alive by health care.” But this particular herd remains sacred. Spending on military benefits is an even more daunting version of the national entitlement debate. Benefits that are deserved are also not sustainable.

With the total budget of the Defense Department likely to decline marginally, and with a larger portion of that budget devoured by pensions and health care, there is likely to be serious downward pressure on research, combat systems, training, operations and maintenance. This is the source of Gates’s alarm: asking the military to do the same missions without sufficient modern equipment and training to do those missions well. “What I am really working against here,” he says, “is what we did in the ’70s and in the ’90s, which was these across-the-board cuts that hollowed out the force.”

In the decade that came between, the Reagan defense buildup produced a new generation of weapons systems that still define the force today — Bradley Fighting Vehicles, Apache attack helicopters, F-15 fighters. But these platforms are old — and now worn from use in Iraq and Afghanistan. In contrast, the large budget increases of the past decade were mainly consumed by overhead, personnel and maintenance costs. With a few exceptions, such as the F-22, spending did not result in new weapons systems.

So the military needs to recover from past and continuing exertions. It also needs, according to Gates, some updated systems and capabilities — a new refueling tanker, effective missile defenses, and new generations of stealth fighters and submarines equipped with ballistic missiles. Under these circumstances, it is not enough for politicians — including the president — to pull defense reduction targets out of thin air. They will need to specify which capabilities and commitments America should abandon.

This splash of cold water is Bob Gates’s last official service to a nation he has served so ably.

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